html {
  box-sizing: border-box;
  min-height: 100vh;
  display: flex;  /*弹性格式化上下文*/
  justify-content: center; /*盒子*/
  align-items: center;
  /* vertical-align: center; 兄弟间的居中 */
  text-align: center; /*行内居中*/
}
*, *::before, *::after {
  box-sizing: inherit;
}
.wrapper {
  padding: 20px;
  max-width: 350px;
  background-color: rgba(255,255,255,0.95);
  box-shadow: 0 0 0 10px rgba(0, 0, 0, 0.1);
}
h2 {
  text-align: center;
  margin: 0;
  font-weight: 200;
}
.plates {
  margin: 0;
  padding: 0;
  text-align: left;
  list-style: none;
}
.plates li {
  border-bottom: 1px solid rgba(0, 0, 0, 0.2);
  padding: 10px 0;
  font-weight: 100;
  display: flex;/*设置弹性格式化上下文*/
}
.plates label {
  flex: 1;
  cursor: pointer;
}
.plates input {
  display: none;
}
.plates input + label::before {
   content: "⬜️";
   margin-right: 10px;
}
.plates input:checked + label::before {
   content: "✅";
}
.add-items {
  margin-top: 20px;
}
.add-items input {
  padding: 10px;
  outline: 5px solid rgba(14,14,211,0.8);
  border: 1px solid rgba(0, 0, 0, 0.1);
}